Screw compressor having rotor casing with removable discharge opening neighborhood portion

Abstract

A screw compressor includes a pair of male and female screw rotors which meshes with each other, where a casing storing the pair of screw rotors is divided into a discharge opening neighborhood portion including at least a discharge opening and an other portion other than the discharge opening neighborhood portion, the discharge opening neighborhood portion is configured so as to be removable from the other portion, further, the casing is divided, by two dividing surfaces orthogonal to rotor shafts, into three portions including a rotor casing around the pair of screw rotors, a discharge casing on a side of the discharge opening, and a suction casing on a side of a suction opening, and the discharge opening neighborhood portion is formed by dividing the rotor casing, and is configured so as to be removable from the dividing surface on the side of the discharge opening of a divided rotor casing. According to this configuration, the number of man-hours required for production thereof is reduced, and if operation conditions change, the size of a discharge opening can be easily changed.

What is claimed is: 
     
       1. A screw compressor comprising:
 a pair of male and female screw rotors that mesh with each other; and 
 a compressor casing that stores said pair of screw rotors, wherein the compressor casing is divided, by dividing surfaces orthogonal to rotor shafts of said pair of screw rotors, into a rotor casing around said pair of screw rotors, a discharge casing on a side of a discharge opening, and a suction casing on a side of a suction opening, 
 wherein said rotor casing is divided into a discharge opening neighborhood portion comprising at least said discharge opening, and a remaining rotor casing portion other than said discharge opening neighborhood portion, and is configured so that said discharge opening neighborhood portion of said rotor casing is removable from said remaining rotor casing portion of said rotor casing, whereby said suction casing and said discharge casing need not be replaced when the performance of the screw compressor is changed. 
 
     
     
       2. The screw compressor according to  claim 1 , wherein:
 said discharge opening neighborhood portion is removable from said dividing surface on the side of said discharge opening of said rotor casing. 
 
     
     
       3. The screw compressor according to  claim 1 , wherein:
 a length, in a direction of said rotor shafts, of said discharge opening neighborhood portion is approximately the same as a length, in the direction of said rotor shafts, of said rotor casing, and 
 said discharge opening neighborhood portion is configured so as to be removable from either one of said dividing surfaces on the side of said discharge opening and on the side of said suction opening of said rotor casing. 
 
     
     
       4. The screw compressor according to  claim 1 , wherein:
 a length, in a direction of said rotor shafts, of said discharge opening neighborhood portion is approximately the same as a length of said rotors, and 
 said discharge opening neighborhood portion is configured so as to be removable from said dividing surface on the side of said suction opening of said rotor casing. 
 
     
     
       5. The screw compressor according to  claim 1 , wherein said rotor casing is configured so that said discharge opening neighborhood portion is removable from said remaining rotor casing portion at least one of the dividing surfaces and in the direction of the rotational axis of the pair of screw rotors. 
     
     
       6. A screw compressor comprising:
 a pair of male and female screw rotors that mesh with each other; and 
 a compressor casing that stores said pair of screw rotors, wherein the compressor casing is divided, by a dividing surface orthogonal to rotor shafts of said pair of screw rotors, into a discharge side rotor casing around said pair of screw rotors and on a side of a discharge opening, and a suction casing on a side of a suction opening, 
 wherein said rotor casing is divided into a discharge opening neighborhood portion comprising at least said discharge opening, and a remaining rotor discharge side casing portion other than said discharge opening neighborhood portion, and is configured so that said discharge opening neighborhood portion of said discharge side rotor casing is removable from said remaining discharge side rotor casing portion of said discharge side rotor casing, whereby said suction casing need not be replaced when the performance of the screw compressor is changed, 
 wherein a length, in a direction of said rotor shafts, of said discharge opening neighborhood portion is approximately the same as a length of said pair of screw rotors, and 
 said discharge opening neighborhood portion is configured so as to be removable from said dividing surface on the side of said suction opening of said divided discharge side rotor casing.